Modle 77 clip fed|Winchester .22 Rim Fire|Forum|Winchester Collector

I recently did a total teardown on my uncle’s 77 he purchased after returning home from Korea in the 50s . Sonic cleaned everything and ordered a used stock and barrel from Numrich. Both in better than expected conditions. One thing I’m puzzled on is a extra pin hole on the right side of the barrel not consistent with the the original. Can anyone give me insite on this as I would like keep it as close to original as possible. He washed the original out shooting bird shot thru it .LOL